A house fire in Toowoomba, west of Brisbane, that claimed the life of a toddler and left four other children in hospital, is not being treated as suspicious, police say.

The single-storey house in Toowoomba was well alight when emergency services arrived on Thursday about 6pm. Firefighters searched the burning house and found a two-year-old boy's body. Two other boys and two girls aged between seven and 15 were taken to Toowoomba hospital to be treated for smoke inhalation.

Detective, acting Snr Sgt Scott Stahlhut, told reporters on Friday the blaze was not being treated as suspicious. He could not confirm whether the children were home alone when the fire started, or whether neighbours broke into the burning home to help them.

"I know there was great community concern and that many people ... assisted where they could," Stahlhut said. He also could not confirm that the fire started in the kitchen.

Fire investigators were at the scene on Friday, and a report was being prepared for the coroner.